1. Field of the Invention
The present invention relates to a lens apparatus and an image pickup apparatus including the lens apparatus, and more particularly, to a lens apparatus including a correction unit for correcting an image blur.
2. Description of the Related Art
Conventionally, as for a unit for correcting a blur in a picked-up image (hereinafter, referred to as “image blur”), there has been used a method of correcting an image blur by detecting vibration by use of a vibration detection device provided in a lens apparatus, and by performing driving control of a correction optical system including correction lens units and image pickup elements based on information from the vibration detection device to correct the image blur.
Some of the lens apparatuses including the image-blur correction unit of this type include an engaging unit for engaging the correction optical system when image-blur correction is not performed or when a power source of the lens apparatus is turned off. The engaging unit is provided for preventing the correction optical system from being broken by disturbances. In many cases, particularly when the power source is turned off, the lens apparatus is in an environment of being liable to be influenced by the disturbances, specifically, in a state of being conveyed. Thus, there have been proposed some methods of shifting the correction optical system of the image-blur correction apparatus into the engage state when the driving control of the correction optical system is completed.
For example, Japanese Patent Application Laid-Open No. 2002-318400 discloses a method of automatically shifting the correction optical system into the engage state with a spring force by using an electromagnetic clutch for maintaining a disengage state such that the correction optical system can be operated, and by stopping electric power supply to the electromagnetic clutch when the driving control of the correction optical system for image-blur correction is completed.
However, according to the related art disclosed in Japanese Patent Application Laid-Open No. 2002-318400 mentioned above, it is necessary to continue electric power supply constantly to the electromagnetic clutch while the image-blur correction unit is enabled. Thus, electric power consumption while the image-blur correction unit is enabled increases.
Therefore, it is an object of the present invention to provide a lens apparatus and an image pickup apparatus including the lens apparatus, which contribute to reduction of the electric power consumption of the correction optical system under a movable state and in which the correction optical system can be shifted into the engage state when the driving control of the correction optical system is completed.